Javascript tutorial 404's

<%= @topic_view.topic.title %>
<%= @topic_view.topic.average_rating %> <%= @topic_view.topic.posts.count { |p| !!p.custom_fields['rating'] } %>

For the javascript tutorial:

Basic Data Structures: Iterate Through the Keys of an Object with a for…in Statement

the “get a hint” link 404’s:

https://guide.freecodecamp.org/certifications/javascript-algorithms-and-data-structures/basic-data-structures/-iterate-through-the-keys-of-an-object-with-a-for---in-statement